#include <iostream>



class student
{
public:
    student();
    student(int a);
    void setage(int a);
    int getage();
    ~student();

private:
    int age;
    int id;
    int grade;
};

student::student()
{
    printf("this is student()\n");
}

student::student(int a)
{
    printf("this is student(a)\n");
    age=a;
}

void student::setage(int a)
{
    
    age=a;
}
int student::getage()
{
    return age;
}

student::~student()
{
    printf("this is ~student()\n");
}

int main()
{
    student stu0;
    student stu1(20);
    // stu1.setage(18);
    printf("%d\n",stu1.getage());
    return  0;
}
